1. Field of Invention
The invention relates to a system debug method and, in particular, to a method used in a computer system for debugging the system through a USB (universal serial bus).
2. Related Art
In the modern world, more and more functions are provided in information processing systems. Therefore, debugging becomes increasingly difficult when problems occur to the system. During the developing phase of a system program or when the system is out of order, debugging is then extremely messy for programmers or ordinary users.
To avoid any possible bugs from occurring for the information processing system to function correctly, any abnormal phenomenon has to be monitored and corrected so that no serious consequences will happen in the information processing system. Conventional programmers or ordinary users have to search for bugs by trials when the system has errors. This often wastes a lot of time and efforts.
To solve the above-mentioned problem, various kinds of debuggers are used as programming tools to help debugging. However, these methods require expensive devices, such as the ICE (in-circuit emulator). This will greatly increase the cost. Another method is to use an I/O (input/output) port connecting to a decoding circuit for debugging. Though the cost of the later method is lower, it is nevertheless very inconvenient because an extra connecting circuit is needed.
From the above description, one sees that currently available debugging utilities are either too costly or too inconvenient in practice. Therefore, it is highly desirable to provide a debugging utility that is both convenient and cheap.